Fishless Cycling For People Who Don't Understand Fishless Cycling

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xoedusk

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I've noticed a more than a few fellow members say that they tried reading up on fishless cycling, but don't get it, and so chose to go with the fishfull cycling. I'd like to attempt to explain in a way that is as clear and simple as possible. It won't be an exhaustive explanation, but hopefully it will give you an idea of what it is all about, and then those other articles will make more sense.

It provides a link to the pinned topic in this Beginner's section, so I see it as a primer to reading the pinned topic.

Read This If Fishless Cycling Sounds Greek To You

There are just four (4) sections here. If you are still a little iffy on the whole subject of cycling in general, read the whole thing, one section at a time. Read and understand each of them before going on to the next. If you are already comfortable with cycling, and just want to learn how one does fishless cycling, skip to section 3.

1. What is cycling? Why is it important?

Fish create waste. It's the same thing when you head to the bathroom. Their waste contains a high amount of a substance called ammonia, which is toxic to fish. If you were to leave a fish in a small bowl for long enough, the ammonia levels would eventually kill them.

This is where cycling comes in. A cycled tank has the ability to do away with this fish-killing ammonia. Cycling a tank, then, is the process by which you make your tank cycled. Now, if those last two sentences passed you by, I'll try again to re-explain it:
  • A cycled tank does away with the toxic ammonia produced by fish.
  • Cycling your tank means making your tank cycled, safe for fish.
Hopefully you now know what cycling is (making your tank have the ability to remove toxic ammonia that is produced by fish), and why it is important (if your tank isn't cycled, your fish will die - I'm sure you're not getting into fishkeeping to keep your future fish happy and healthy). By cycling, you are making your tank safe for fish before you add them to your tank. Once your fish are added, they will keep the tank cycled themselves. You're just getting their home ready; once they're in, they'll keep it up.

(Now cycling is a funny word to describe it, I know. I personally had a bit of reservation and difficulty in trying to understand cycling because of its name. It's name just doesn't make any sense! Well, it does. Sort of. Read on!)

2. How does cycling work?

So now you have an understanding of what cycling is, and why it is important for the health of your fish. But just how does it work? Well, the key players here are bacteria. Yes, bacteria, the thing we all fear. But they're not all that bad - after all, they let us have cheese and half-n-half. Anyway, get prepared for the following paragraphs, which explains how cycling works.

A certain type of bacterium thrives on ammonia - they actually eat the stuff! This is wonderful! Bacteria will eat the stuff that kills our fish, namely ammonia. And just where is this magical bacteria located? It's on all the surfaces of your tank, especially the gravel or your inside your filter (they love it in there).

Now this bacteria that eats ammonia has a down side - it itself produces waste, called nitrite, and this nitrite is also toxic to fish. To summarize, bacteria eats toxic ammonia, and as a by-product produces toxic nitrite. Bummer. Luckly, however, this nitrite is less toxic to fish, so we're at least going in the right direction. There is just one more step to fully understanding how cycling works, so hang in there.

We have to do something about this toxic nitrite, because it will also kill your fish. Any ideas? Well, we are in luck - there is a different type of bacterium that eats nitrite, and this nitrite-eating bacteria will also live in your tank alongside the ammonia-eating bacteria. This new nitrite-eating bacteria also produces waste, namely nitrate. (That's nitrate with an A, not an I as in nitrite. Keep them separate in your head!) This nitrate is the end of the line for us - it won't be eaten by any other type of bacterium and is safe in low concentrations.

But nitrate (with an A) is not safe in high concentrations! But we just have to do weekly water changes of say 25% of the total tank volume to keep it down. And that's all there is to understanding how cycling works! I did say a lot in this section, so a summary is in order:
  • Ammonia is toxic to your fish
  • A particular type of bacterium eats ammonia, producing nitrite (with an I) as a by-product
  • Nitrite is toxic to your fish
  • A different type of bacterium eats nitrite, producing nitrate (with an A) as a by-product
  • Nitrates must be removed by weekly water changes
Now we have a better way to explain cycling: cycling is the process by which you establish these beneficial bacteria, which turn toxic fish waste into nitrite, then nitrate. A cycled tank, then, is a tank that has a sufficient amount of these bacteria to never have toxic levels of ammonia or nitrite (with an I), with the bacteria usually living in your rocks/gravel/sand and your filter. In a cycled tank, you will never be able to detect ammonia or nitrite, but you will be able to detect nitrate.

3. Understanding Fishless Cycling

We now know that fish produce ammonia (toxic), which is turned into nitrite (less toxic), which is turned into nitrate (least toxic). You are now in a position to understand how actually to cycle your tank - how to establish, or grow if you will, these bacteria that your fish so desperately need in order to survive.

The term fishless cycling implies there is a different type of cycling with fish, which is true. The latter is usually given just the term "cycling," while when one cycles a tank without fish, it is usually always denoted by "fishless cycling." We will only deal with the fishless version of cycling. In this section I will explain the procedure in general, then go into detail in the last section.

The key to fishless cycling is getting your hands on a solution of ammonia, usually from a hardware store or supermarket (try Home Depot, Wal-Mart, Home Base). It's important that the bottle you buy contains only ammonia (ammonium hydroxide) and water. No fragrances, no surficants, no colorings, no fragrances, no colorings, no surficants, no colorings. Did I mention no fragrances? This way, when you complete your fishless cycle (completing means establishing plenty of beneficial bacteria), there won't be a build-up of these chemical nasties, which would surely kill your fish.

To perform a fishless cycling, you'll need a few supplies:
  • Pure ammonia, as just mentioned
  • Ammonia, Nitrite, Nitrate, and pH testing kits, sold at your local fish store (LFS). Liquid tests are more accurate than the strip-type.
  • A simple dechlorinator, also sold at your LFS.
  • Some way of accurately measuring small amounts of your ammonia solution, like an eye-dropper. Small measuring-cups may work.
  • 10 minutes per day
Now you're ready. Remember, this section is just an overview. Read this section carfully, then move on to section four for detailed information

Fishless cycling begins with you adding ammonia to your tank. The ammonia-eating bacteria will slowly establish itself in your tank, eating this stuff. You always want to keep at least some ammonia in your tank so the bacteria have something to feed on and don't starve before the cycling process is done. As you do this (continue adding ammonia to keep the ammonia concentration above zero), the ammonia-eating bacteria will produce nitrite (with an I) as waste. This nitrite, then, becomes food for the nitrite-eating bacteria, which will again slowly establish itself in your tank. This usually takes twice as long to establish as the ammonia-eating bacteria.

This is really all there is to fishless cycling: you add ammonia to feed bacteria, which produce nitrite as waste. This nitrite is food for a different bacteria, which produce nitrate as waste. The tricky thing to remember is to never let your ammonia concentration fall to zero for more than 12 hours, otherwise your precious colony will die of starvation. This doesn't mean you have to feed your tank every 12 hours; the details are in the next section. As a check that you are completing the ammonia to nitrite, then nitrite to nitrate cycle, you can test for increased levels of nitrate.

Here, again, is a very brief summary of how fishless cycling works:
  • You need to establish both ammonia-eating and nitrite-eating bacteria
  • So you add pure ammonia to your tank to feed the ammonia-eating type,
  • which produce nitrite as waste, which feeds the nitrite-eating type,
  • which produces nitrate as waste,
  • which needs to be removed with weekly water changes.
This is a neat little system: you add ammonia to feed bacteria. This bacteria produces nitrite as waste, which is eaten by a different type of bacteria, the nitrite-eating bacteria. So you are indirectly feeding the nitrite-eating bacteria.

Just a few words before you are ready for detailed instructions. Your tank will not fully cycle if your water's pH is below 6. I recommend occasionally testing your pH to see if there are any problems. Ask on these forums if you find your pH too low, and we'll help you get it sorted out.

4. Details of the Fishless Cycle

You are now at a point to fully understand how to perform a fishless cycle. There are many articles on the web that give advice. The clearest and easiest to understand one I've read is right here on these forums, in the pinned topics of the Beginners section. Here is a link to it - I recommed the "Add and Wait" Method. It explains it in a way I could never hope to. One word of caution: I disagree with not testing your pH during the cycle. Your cycle can stall if the pH drops below 6 - that is if your water becomes too acidic. I recommend testing occasionally.

Now be off and read that pinned topic. And remember to use the Beginner's section to ask questions!
 

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